[Intel-gfx] [PATCH] drm/i915: page table abstractions
Michel Thierry
michel.thierry at intel.com
Tue Feb 24 03:14:22 PST 2015
From: Ben Widawsky <benjamin.widawsky at intel.com>
When we move to dynamic page allocation, keeping page_directory and pagetabs as
separate structures will help to break actions into simpler tasks.
To help transition the code nicely there is some wasted space in gen6/7.
This will be ameliorated shortly.
Following the x86 pagetable terminology:
PDPE = struct i915_page_directory_pointer_entry.
PDE = struct i915_page_directory_entry [page_directory].
PTE = struct i915_page_table_entry [page_tables].
v2: fixed mismatches after clean-up/rebase.
v3: Clarify the names of the multiple levels of page tables (Daniel)
v4: Addressing Mika's review comments.
s/gen8_free_page_directories/gen8_free_page_directory and free the
page tables for the directory there.
In gen8_ppgtt_allocate_page_directories, do not leak previously allocated
pt in case the page_directory alloc fails.
Update error return handling in gen8_ppgtt_alloc.
v5: Do not leak pt on error in gen6_ppgtt_allocate_page_tables. (Mika)
Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
Signed-off-by: Michel Thierry <michel.thierry at intel.com> (v2+)
---
drivers/gpu/drm/i915/i915_gem_gtt.c | 180 +++++++++++++++++++-----------------
drivers/gpu/drm/i915/i915_gem_gtt.h | 23 ++++-
2 files changed, 111 insertions(+), 92 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index e54b2a0..b4dee34 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -338,7 +338,8 @@ static void gen8_ppgtt_clear_range(struct i915_address_space *vm,
I915_CACHE_LLC, use_scratch);
while (num_entries) {
- struct page *page_table = ppgtt->gen8_pt_pages[pdpe][pde];
+ struct i915_page_directory_entry *pd = &ppgtt->pdp.page_directory[pdpe];
+ struct page *page_table = pd->page_tables[pde].page;
last_pte = pte + num_entries;
if (last_pte > GEN8_PTES_PER_PAGE)
@@ -382,8 +383,12 @@ static void gen8_ppgtt_insert_entries(struct i915_address_space *vm,
if (WARN_ON(pdpe >= GEN8_LEGACY_PDPES))
break;
- if (pt_vaddr == NULL)
- pt_vaddr = kmap_atomic(ppgtt->gen8_pt_pages[pdpe][pde]);
+ if (pt_vaddr == NULL) {
+ struct i915_page_directory_entry *pd = &ppgtt->pdp.page_directory[pdpe];
+ struct page *page_table = pd->page_tables[pde].page;
+
+ pt_vaddr = kmap_atomic(page_table);
+ }
pt_vaddr[pte] =
gen8_pte_encode(sg_page_iter_dma_address(&sg_iter),
@@ -407,29 +412,33 @@ static void gen8_ppgtt_insert_entries(struct i915_address_space *vm,
}
}
-static void gen8_free_page_tables(struct page **pt_pages)
+static void gen8_free_page_tables(struct i915_page_directory_entry *pd)
{
int i;
- if (pt_pages == NULL)
+ if (pd->page_tables == NULL)
return;
for (i = 0; i < GEN8_PDES_PER_PAGE; i++)
- if (pt_pages[i])
- __free_pages(pt_pages[i], 0);
+ if (pd->page_tables[i].page)
+ __free_page(pd->page_tables[i].page);
}
-static void gen8_ppgtt_free(const struct i915_hw_ppgtt *ppgtt)
+static void gen8_free_page_directory(struct i915_page_directory_entry *pd)
+{
+ gen8_free_page_tables(pd);
+ kfree(pd->page_tables);
+ __free_page(pd->page);
+}
+
+static void gen8_ppgtt_free(struct i915_hw_ppgtt *ppgtt)
{
int i;
for (i = 0; i < ppgtt->num_pd_pages; i++) {
- gen8_free_page_tables(ppgtt->gen8_pt_pages[i]);
- kfree(ppgtt->gen8_pt_pages[i]);
+ gen8_free_page_directory(&ppgtt->pdp.page_directory[i]);
kfree(ppgtt->gen8_pt_dma_addr[i]);
}
-
- __free_pages(ppgtt->pd_pages, get_order(ppgtt->num_pd_pages << PAGE_SHIFT));
}
static void gen8_ppgtt_unmap_pages(struct i915_hw_ppgtt *ppgtt)
@@ -464,86 +473,77 @@ static void gen8_ppgtt_cleanup(struct i915_address_space *vm)
gen8_ppgtt_free(ppgtt);
}
-static struct page **__gen8_alloc_page_tables(void)
+static int gen8_ppgtt_allocate_dma(struct i915_hw_ppgtt *ppgtt)
{
- struct page **pt_pages;
int i;
- pt_pages = kcalloc(GEN8_PDES_PER_PAGE, sizeof(struct page *), GFP_KERNEL);
- if (!pt_pages)
- return ERR_PTR(-ENOMEM);
-
- for (i = 0; i < GEN8_PDES_PER_PAGE; i++) {
- pt_pages[i] = alloc_page(GFP_KERNEL);
- if (!pt_pages[i])
- goto bail;
+ for (i = 0; i < ppgtt->num_pd_pages; i++) {
+ ppgtt->gen8_pt_dma_addr[i] = kcalloc(GEN8_PDES_PER_PAGE,
+ sizeof(dma_addr_t),
+ GFP_KERNEL);
+ if (!ppgtt->gen8_pt_dma_addr[i])
+ return -ENOMEM;
}
- return pt_pages;
-
-bail:
- gen8_free_page_tables(pt_pages);
- kfree(pt_pages);
- return ERR_PTR(-ENOMEM);
+ return 0;
}
-static int gen8_ppgtt_allocate_page_tables(struct i915_hw_ppgtt *ppgtt,
- const int max_pdp)
+static int gen8_ppgtt_allocate_page_tables(struct i915_hw_ppgtt *ppgtt)
{
- struct page **pt_pages[GEN8_LEGACY_PDPES];
- int i, ret;
+ int i, j;
- for (i = 0; i < max_pdp; i++) {
- pt_pages[i] = __gen8_alloc_page_tables();
- if (IS_ERR(pt_pages[i])) {
- ret = PTR_ERR(pt_pages[i]);
- goto unwind_out;
+ for (i = 0; i < ppgtt->num_pd_pages; i++) {
+ for (j = 0; j < GEN8_PDES_PER_PAGE; j++) {
+ struct i915_page_table_entry *pt = &ppgtt->pdp.page_directory[i].page_tables[j];
+
+ pt->page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ if (!pt->page)
+ goto unwind_out;
}
}
- /* NB: Avoid touching gen8_pt_pages until last to keep the allocation,
- * "atomic" - for cleanup purposes.
- */
- for (i = 0; i < max_pdp; i++)
- ppgtt->gen8_pt_pages[i] = pt_pages[i];
-
return 0;
unwind_out:
- while (i--) {
- gen8_free_page_tables(pt_pages[i]);
- kfree(pt_pages[i]);
- }
+ while (i--)
+ gen8_free_page_tables(&ppgtt->pdp.page_directory[i]);
- return ret;
+ return -ENOMEM;
}
-static int gen8_ppgtt_allocate_dma(struct i915_hw_ppgtt *ppgtt)
+static int gen8_ppgtt_allocate_page_directories(struct i915_hw_ppgtt *ppgtt,
+ const int max_pdp)
{
int i;
- for (i = 0; i < ppgtt->num_pd_pages; i++) {
- ppgtt->gen8_pt_dma_addr[i] = kcalloc(GEN8_PDES_PER_PAGE,
- sizeof(dma_addr_t),
- GFP_KERNEL);
- if (!ppgtt->gen8_pt_dma_addr[i])
- return -ENOMEM;
- }
+ for (i = 0; i < max_pdp; i++) {
+ struct i915_page_table_entry *pt;
- return 0;
-}
+ pt = kcalloc(GEN8_PDES_PER_PAGE, sizeof(*pt), GFP_KERNEL);
+ if (!pt)
+ goto unwind_out;
-static int gen8_ppgtt_allocate_page_directories(struct i915_hw_ppgtt *ppgtt,
- const int max_pdp)
-{
- ppgtt->pd_pages = alloc_pages(GFP_KERNEL, get_order(max_pdp << PAGE_SHIFT));
- if (!ppgtt->pd_pages)
- return -ENOMEM;
+ ppgtt->pdp.page_directory[i].page = alloc_page(GFP_KERNEL);
+ if (!ppgtt->pdp.page_directory[i].page) {
+ kfree(pt);
+ goto unwind_out;
+ }
+
+ ppgtt->pdp.page_directory[i].page_tables = pt;
+ }
- ppgtt->num_pd_pages = 1 << get_order(max_pdp << PAGE_SHIFT);
+ ppgtt->num_pd_pages = max_pdp;
BUG_ON(ppgtt->num_pd_pages > GEN8_LEGACY_PDPES);
return 0;
+
+unwind_out:
+ while (i--) {
+ kfree(ppgtt->pdp.page_directory[i].page_tables);
+ __free_page(ppgtt->pdp.page_directory[i].page);
+ }
+
+ return -ENOMEM;
}
static int gen8_ppgtt_alloc(struct i915_hw_ppgtt *ppgtt,
@@ -555,18 +555,20 @@ static int gen8_ppgtt_alloc(struct i915_hw_ppgtt *ppgtt,
if (ret)
return ret;
- ret = gen8_ppgtt_allocate_page_tables(ppgtt, max_pdp);
- if (ret) {
- __free_pages(ppgtt->pd_pages, get_order(max_pdp << PAGE_SHIFT));
- return ret;
- }
+ ret = gen8_ppgtt_allocate_page_tables(ppgtt);
+ if (ret)
+ goto err_out;
ppgtt->num_pd_entries = max_pdp * GEN8_PDES_PER_PAGE;
ret = gen8_ppgtt_allocate_dma(ppgtt);
if (ret)
- gen8_ppgtt_free(ppgtt);
+ goto err_out;
+
+ return 0;
+err_out:
+ gen8_ppgtt_free(ppgtt);
return ret;
}
@@ -577,7 +579,7 @@ static int gen8_ppgtt_setup_page_directories(struct i915_hw_ppgtt *ppgtt,
int ret;
pd_addr = pci_map_page(ppgtt->base.dev->pdev,
- &ppgtt->pd_pages[pd], 0,
+ ppgtt->pdp.page_directory[pd].page, 0,
PAGE_SIZE, PCI_DMA_BIDIRECTIONAL);
ret = pci_dma_mapping_error(ppgtt->base.dev->pdev, pd_addr);
@@ -597,7 +599,7 @@ static int gen8_ppgtt_setup_page_tables(struct i915_hw_ppgtt *ppgtt,
struct page *p;
int ret;
- p = ppgtt->gen8_pt_pages[pd][pt];
+ p = ppgtt->pdp.page_directory[pd].page_tables[pt].page;
pt_addr = pci_map_page(ppgtt->base.dev->pdev,
p, 0, PAGE_SIZE, PCI_DMA_BIDIRECTIONAL);
ret = pci_dma_mapping_error(ppgtt->base.dev->pdev, pt_addr);
@@ -658,7 +660,7 @@ static int gen8_ppgtt_init(struct i915_hw_ppgtt *ppgtt, uint64_t size)
*/
for (i = 0; i < max_pdp; i++) {
gen8_ppgtt_pde_t *pd_vaddr;
- pd_vaddr = kmap_atomic(&ppgtt->pd_pages[i]);
+ pd_vaddr = kmap_atomic(ppgtt->pdp.page_directory[i].page);
for (j = 0; j < GEN8_PDES_PER_PAGE; j++) {
dma_addr_t addr = ppgtt->gen8_pt_dma_addr[i][j];
pd_vaddr[j] = gen8_pde_encode(ppgtt->base.dev, addr,
@@ -721,7 +723,7 @@ static void gen6_dump_ppgtt(struct i915_hw_ppgtt *ppgtt, struct seq_file *m)
expected);
seq_printf(m, "\tPDE: %x\n", pd_entry);
- pt_vaddr = kmap_atomic(ppgtt->pt_pages[pde]);
+ pt_vaddr = kmap_atomic(ppgtt->pd.page_tables[pde].page);
for (pte = 0; pte < I915_PPGTT_PT_ENTRIES; pte+=4) {
unsigned long va =
(pde * PAGE_SIZE * I915_PPGTT_PT_ENTRIES) +
@@ -936,7 +938,7 @@ static void gen6_ppgtt_clear_range(struct i915_address_space *vm,
if (last_pte > I915_PPGTT_PT_ENTRIES)
last_pte = I915_PPGTT_PT_ENTRIES;
- pt_vaddr = kmap_atomic(ppgtt->pt_pages[act_pt]);
+ pt_vaddr = kmap_atomic(ppgtt->pd.page_tables[act_pt].page);
for (i = first_pte; i < last_pte; i++)
pt_vaddr[i] = scratch_pte;
@@ -965,7 +967,7 @@ static void gen6_ppgtt_insert_entries(struct i915_address_space *vm,
pt_vaddr = NULL;
for_each_sg_page(pages->sgl, &sg_iter, pages->nents, 0) {
if (pt_vaddr == NULL)
- pt_vaddr = kmap_atomic(ppgtt->pt_pages[act_pt]);
+ pt_vaddr = kmap_atomic(ppgtt->pd.page_tables[act_pt].page);
pt_vaddr[act_pte] =
vm->pte_encode(sg_page_iter_dma_address(&sg_iter),
@@ -1000,8 +1002,9 @@ static void gen6_ppgtt_free(struct i915_hw_ppgtt *ppgtt)
kfree(ppgtt->pt_dma_addr);
for (i = 0; i < ppgtt->num_pd_entries; i++)
- __free_page(ppgtt->pt_pages[i]);
- kfree(ppgtt->pt_pages);
+ if (ppgtt->pd.page_tables[i].page)
+ __free_page(ppgtt->pd.page_tables[i].page);
+ kfree(ppgtt->pd.page_tables);
}
static void gen6_ppgtt_cleanup(struct i915_address_space *vm)
@@ -1058,17 +1061,18 @@ alloc:
static int gen6_ppgtt_allocate_page_tables(struct i915_hw_ppgtt *ppgtt)
{
+ struct i915_page_table_entry *pt;
int i;
- ppgtt->pt_pages = kcalloc(ppgtt->num_pd_entries, sizeof(struct page *),
- GFP_KERNEL);
-
- if (!ppgtt->pt_pages)
+ pt = kcalloc(ppgtt->num_pd_entries, sizeof(*pt), GFP_KERNEL);
+ if (!pt)
return -ENOMEM;
+ ppgtt->pd.page_tables = pt;
+
for (i = 0; i < ppgtt->num_pd_entries; i++) {
- ppgtt->pt_pages[i] = alloc_page(GFP_KERNEL);
- if (!ppgtt->pt_pages[i]) {
+ pt[i].page = alloc_page(GFP_KERNEL);
+ if (!pt->page) {
gen6_ppgtt_free(ppgtt);
return -ENOMEM;
}
@@ -1108,9 +1112,11 @@ static int gen6_ppgtt_setup_page_tables(struct i915_hw_ppgtt *ppgtt)
int i;
for (i = 0; i < ppgtt->num_pd_entries; i++) {
+ struct page *page;
dma_addr_t pt_addr;
- pt_addr = pci_map_page(dev->pdev, ppgtt->pt_pages[i], 0, 4096,
+ page = ppgtt->pd.page_tables[i].page;
+ pt_addr = pci_map_page(dev->pdev, page, 0, 4096,
PCI_DMA_BIDIRECTIONAL);
if (pci_dma_mapping_error(dev->pdev, pt_addr)) {
@@ -1157,7 +1163,7 @@ static int gen6_ppgtt_init(struct i915_hw_ppgtt *ppgtt)
ppgtt->base.insert_entries = gen6_ppgtt_insert_entries;
ppgtt->base.cleanup = gen6_ppgtt_cleanup;
ppgtt->base.start = 0;
- ppgtt->base.total = ppgtt->num_pd_entries * I915_PPGTT_PT_ENTRIES * PAGE_SIZE;
+ ppgtt->base.total = ppgtt->num_pd_entries * I915_PPGTT_PT_ENTRIES * PAGE_SIZE;
ppgtt->debug_dump = gen6_dump_ppgtt;
ppgtt->pd_offset =
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index 8f76990..d9bc375 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -187,6 +187,20 @@ struct i915_vma {
u32 flags);
};
+struct i915_page_table_entry {
+ struct page *page;
+};
+
+struct i915_page_directory_entry {
+ struct page *page; /* NULL for GEN6-GEN7 */
+ struct i915_page_table_entry *page_tables;
+};
+
+struct i915_page_directory_pointer_entry {
+ /* struct page *page; */
+ struct i915_page_directory_entry page_directory[GEN8_LEGACY_PDPES];
+};
+
struct i915_address_space {
struct drm_mm mm;
struct drm_device *dev;
@@ -272,11 +286,6 @@ struct i915_hw_ppgtt {
unsigned num_pd_entries;
unsigned num_pd_pages; /* gen8+ */
union {
- struct page **pt_pages;
- struct page **gen8_pt_pages[GEN8_LEGACY_PDPES];
- };
- struct page *pd_pages;
- union {
uint32_t pd_offset;
dma_addr_t pd_dma_addr[GEN8_LEGACY_PDPES];
};
@@ -284,6 +293,10 @@ struct i915_hw_ppgtt {
dma_addr_t *pt_dma_addr;
dma_addr_t *gen8_pt_dma_addr[GEN8_LEGACY_PDPES];
};
+ union {
+ struct i915_page_directory_pointer_entry pdp;
+ struct i915_page_directory_entry pd;
+ };
struct drm_i915_file_private *file_priv;
--
2.1.1
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